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Date: Wed, 6 Apr 2016 18:56:37 +0530
From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Anton Blanchard <anton@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@kernel.org>,
 tglx@linutronix.de, efault@gmx.de, htejun@gmail.com,
 linux-kernel@vger.kernel.org, tj@kernel.org,
 torvalds@linux-foundation.org, zhaolei@cn.fujitsu.com,
 yangds.fnst@cn.fujitsu.com, hpa@zytor.com,
 Stephen Rothwell <sfr@canb.auug.org.au>,
 Michael Ellerman <mpe@ellerman.id.au>, linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH] sched/cpuacct: Check for NULL when using task_pt_regs()
Message-ID: <20160406132637.GA2108@linux.vnet.ibm.com>
Reply-To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
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 <tip-d740037fac7052e49450f6fa1454f1144a103b55@git.kernel.org>
 <20160404140312.GA28495@linux.vnet.ibm.com>
 <20160406065436.GB3078@gmail.com> <20160406203219.788ae7cf@kryten>
 <20160406110803.GI2906@worktop> <20160406215950.04bc3f0b@kryten>
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* Anton Blanchard <anton@samba.org> [2016-04-06 21:59:50]:

> Looks good, and the patch below does fix the oops for me.
> 
> Anton
> --
> 
> task_pt_regs() can return NULL for kernel threads, so add a check.
> This fixes an oops at boot on ppc64.
> 
> Signed-off-by: Anton Blanchard <anton@samba.org>

Works for me too.

Reported-and-Tested-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>

-- 
Thanks and Regards
Srikar Dronamraju